(Python, Java) 리트코드 - Valid Parentheses

04 Apr 2022 in Algorithm on Leetcode

[문제 링크]

Python 풀이

class Solution:
    def isValid(self, s: str) -> bool:
        store = {"[": "]", "{": "}", "(": ")"}

        stack = []
        for letter in s:

            # 왼쪽
            if letter in store:
                stack.append(letter)

            # 오른쪽 인데 빈 경우
            elif len(stack) == 0:
                return False

            # 오른쪽인데 안 빈경우
            else:
                pop = stack.pop()
                if store.get(pop) != letter:
                    return False

        return len(stack) == 0

Java 풀이

import java.util.*;

class Solution {

    public boolean isValid(String s) {
        Map<Character, Character> brackets = new HashMap();
        brackets.put('[', ']');
        brackets.put('{', '}');
        brackets.put('(', ')');

        Stack<Character> stack = new Stack<>();
        for (char letter : s.toCharArray()) {
            if (brackets.containsKey(letter))
                stack.add(letter);
            else if (!stack.isEmpty() && brackets.get(stack.peek()) == letter)
                stack.pop();                
            else {
                return false;
            }
        }

        return stack.isEmpty();
    }
}